ELECTRICITY AND CHOLERA. 245 



disease due to a deficiency in the amount of 

 the electricity of the air. Some curious state- 

 ments have been made. At St. Petersburgh it 

 was found that a large magnet had wholly lost 

 its power so long as cholera ravaged the city; 

 but, as the disease took its departure, the mag- 

 net gradually recovered its sustaining effect, 

 and when the disease had entirely gone it was 

 as strong as before. It has also been noticed 

 that the electric telegraph refused to act during 

 its prevalence. The most recent communication 

 on this point is contained in a letter addressed 

 by M. Andraud to the President of the Aca- 

 demy of Sciences (France), of which we give 

 the following extracts. The machine used in the 

 observations was a powerful electric machine,- 

 capable, at ordinary times, of giving out sparks 

 in profusion on being gently put into action. 

 " From the time the epidemic became general," 

 writes M. Andraud, " I was no longer able, on 

 any single occasion, to produce a corresponding 

 effect. During the months of April and May 

 (1849), sparks could only be procured after 

 violent action .... These fluctuations were 

 then observed to coincide most exactly with the 

 fluctuations of the cholera! Nevertheless, I 

 was afraid lest the irregularities of the electric 

 machine should have been occasioned by the 

 hygrometric state of the atmosphere. I waited 



